Strainer.



A. E. KRA USE.

STRAINER. APPLICATION FILED FEB.19,1914.

1, 1 1 1,471, Patented Sept. 22, 1914.

With Lewes vwe Mioz $51,414 M0251? a/am WWW ARTHUR E. KRAUSE, OF JERSEYCITY, NEW JERSEY.

' STRAINER.

- Specification of Letters Patent.

Patented Sept. 22, 1914.

Application filed February s, 1914 Serial No. 819,788.

To all whom it may concern.-

Be it known that I, ARTHUR E. KRAUSE, a citizen of the United States ofAmerica, and a resident of Jersey City, in the county of Hudson andState of New Jersey, have vented certain new and useful Improvements inStrainers, of which the following is a specification.

My invention relates to improvements instrainers, particularly strainerswhich are intended to exclude solid matter while permitting the freeflow of water or other liquid which may carry solid matter with it. Theimproved strainers herein described are particularly intended for use inconnection with filters employing a layer of granular material .(such assand for example) as a. filter bed. In such filters, strainers are used,not only to prevent the particles of the granular material'of the filterbed from entering the clear water outlet pipe, but also for admittingwashed water to the filter bed and distributing such washed water widelythroughout such bed. In such filters, it has been the practiceheretofore to employ a plu' rality of strainer heads, such heads beingeither connectedto a series of communicating pipes under the filter bed,and leading to a common outlet pipe, or being mounted on ageneraldischarge plate beneath the filter bed, there being beneath thisdischarge plate, a discharge chamber, With-Which the clear waterdischarge pipe communicates. When washing the filter bed of such afilter,

the flow of water is reversed; i. e., washing water is caused to flowthrough what is normally the clear water pipe into the strainers andthence into the filter bed, such washing water being discharged, inpractice, into a suitable overflow pipe. By means of the washing waterpassing through the filter bed in the reverse of the direction of normalflow of water through such bed,

the material of said. bed is thoroughly agitated and washed, and therebyfreed from impurities taken up during the filtering op eration. v

The strainer heads commonly used heretofore consist of metallic nozzleshaving saw-cuts orslots forming orifices through which the water passes,such cuts being narrow enough to prevent the particles of filtering sandfrom entering or passing through them with the Water. Other strainerheads have been provided with a number of small holes, in lieu of thesaw-cuts or slots mentioned. These former strainer heads have been soconstructed, as a rule, that only a very limited area of strainingsurface is available, the number of straining slots or holes beingtherefore'small, and the total cross-sectional area of such slots orholes being small, with the result that water passes through such slotsor holes at a relatively high velocity; and since such water is apt tocarry with it gritty matter, the slots or holes are gradually cut orwidened by the action of such gritty matter, with the result that suchstrainers soon require renewal, or a coarser or less efficient grade ofsand must be substituted. In some cases attempt has been made to reduceto a low limit the velocity of the Water through the strainer holes, bythe provision of a very large number of strainers; but this increasesgreatly the cost of the filtering apparatus.

By my invention I provide strainer heads which, even When of moderatesize, have a very large efiective straining area, containing a verylarge total cross section of straining holes or slots, the velocity ofthe water through which will be relatively low, there fore; and thesestrainer heads are of very simple constructlon, and moreover are proidedwith means for preventing the granusequent reduction of tendency of thestrain-- ers to clog, and since the granular material of the filter beddoes not come into immediate contact with the straining surfaces,

there is practically no action tending to cut out or enlarge thestrainer slots.

-My invention consists in the novel construction of thestrainer head,hereinafter described.

The object of my invention is to improve strainer heads and toincreasein proportion to the size of the strainer heads, the totalefiective straining area,'and the total area of straining holes orperforations. Y

I will now proceed to describe my invention with reference to theaccompanying drawings, and will then pointput the .novel.

features in claims.

In the drawings: Figure 1 shows a trans verse section of a filter casinghaving within it a filter bed of granular materialflain'd a of thestrainer head and Fig. 5 shows a side view thereof. Fig. 6 shows a topview of one of the bossed rings of which the side i walls of thestrainer head are built up, and Fig. 7 shows a side view of one of suchrings. Fig. 8 shows a side view of an alternative form of ring. Fig. 9shows a longitudinal section of a strainer having the wall-rings withinthe 'l'llQS instead of outside of said ribs. Fig. 10 is a longitudinalsection of a 1 3. The hood torm shown in Fig. 2 has cerfurtheralternative form of strainer; and

strainer; and Fig. 3 shows a top view of the 5 base portion of thestrainer with the top of i the strainer and the strainer rings removed.In Fig. 1, l designates the filter tank, 3

the strainer heads, a the clear water outlet pipe, and ('3 amanifoldconnected to said: pipe 4 and to which the stralner heads 3 are 5 i butis convenient, since it reinforces these connected. The particular shapeof the tank 1 and the particular arrangement of pipes 47 and (5 therein.and of the strainers on said 1 pipe 6, form no portion of my invention,and may be varied as desired. arrangement of pipes 6 and strainer heads3 thereon should be adopted, such that the strainers are spaced asevenly as possible over the entire cross sectional area of the tank, andwith the strainers at suitable distances from one another. 2 designatesthe granular material of the filter bed.

The strainer heads 3 comprise a body or base portion 10 having asuitable flow connection 11 and having ribs 13 projecting up wardlyfrom, but preferably formed integrally with. the base portion 10. Asindicated particularly in Figs. 3, 4 and 5 these ribs 13 may beconnected, near their upper ends, by an integrally formed ring 13 thefunction of whichwill be referred to hereinafter; although, as indicatedin Fig. 2, this ring 13 may be omitted. The walls of the strainer areformed, in the construction shown, by a series of rings or washers 21 ofsuchinternal diameter that they fit over and are centered by the ribs13. These rings or washers 21 are spaced apart somewhat by any suitablemeans, the particular means indicated, which is very convenient for thepurpose, being bosses 21 provided on the upper and lower surfaces ofsuch rings. These rings may be formed conveniently by stamping them fromsheet metal, and the said bosses may be formed in the rings by theaction of the stamping dies or of other suitable dies. \Vhen the ringsare assembled on the body of the strainer head, they form what is ineifect an annular.toraminous wall, the slots 12 provided between therings 21 as a result of the spacing apart of those rings constitutingopenings in such wall for the passage of the liquid.

The top of the strainer head is closedand the rings 21 are held inplace, by means of a top plate or end piece It (Fig. 2) or 14 (Fig. 3)having a screw threaded portion 15 engaging screw threads on the innerwalls of the ribs 13 (Fig. 2) or on the inner wall of the ring 13 (Figs.3 and 4:) with which ring 13 the ribs 13 are integral as previouslydescribed. The top or end piece of the strainer head may be of hoodform, as shown in Fig. 2, or may be plain, as shown in Fig.

tain advantages, for since the hood projects well out from the body ofthe strainer head, the natural angle-of-repose hillocks of the filterbed, formed by these hoods, clear the straining surface of the strainersand so provide a free space, around the straining surface of thestrainers for the flow of the liquid into the strainers.

The ring 13 connecting the ribs 13 near their upper or outer ends, isnot essential,

ribs 13 and therefore permits the ribs 13 to be of lighter constructionthan would be desirable otherwise, and also since this ring l3 havingcontinuous screw threads on its inner surface, is more easily engaged bythe threads of the boss 15 of the end piece. In the contruction shown inFig. 2, in which no ring 13 connecting the ribs 13 is employed, the ribs13 together constitute in effect a body having an interrupted screwthread; and it, is sometimes diliicult to engage the threads of the boss15 of the end piece with corresponding threads of all of such ribs 13.

The bosses of the rings or washers 21 are, preferably, spacedirregularly, as indicated particularly in-Fig. 6, so as to render itimprobable that the bosses of one ring will be directly over the bossesof the ring beneath. It is preferable that the bosses of the rings shallhave staggered relation.

While I have shown in Figs. 6 and 7, the ring 21 providedwith recessescomplemental to the bosses, it is preferable to form the and such a ringis shown in Fig. 8. It is rings without such complemental recesses;quite practicable to form rings with bosses and without recessescomplemental to those bosses, as sufiicient pressure exerted by theforming dies will cause the metal to flow so as to form bosseswithoutcomplemental recesses'.

As indicated in Fig. 9, the wall rings 21 may be within the ribs 13instead of being outside of such ribs. as indicated in the precedingfigures.

Instead of providing the base 10 with aplurality of upwardly projectingribs 13, the

provided, the velocity of the water passing through these orifices isslow; the advanuages of which have been set forth heretofore.

This application is in part a'continuation of my prior application forLetters Patent for improvements in strainers, filed April 29, 1913, Sr.No. 764,875 in which application I have claimed a strainer comprising'ahollow body having a flow connection and having inwardly pro eet1ngportions and perforations, between such inwardly pro ect1ng portions,extending from the outer. surface of said body inward; the saidinwardprojections (represented in the constructions shown herein by theribs 13) being screw threaded internally; and an end piece having acorrespondingly screw threaded portion engaging the threads of saidprojections, said end piece closing the end of said body. In said priorapplication I have also claimed a strainer comprising a base having aflow connection and having ribs projecting therefrom, a perforate wallsurrounding said ribs, and an end piece structurally separate from saidbase and ribs. detachably connected to said ribs and. closing the wallatits end. Therefore I do not claim such features in this application.

\Vhat I claim. is

l. A strainer such as described comprising a base provided with integralprojecting ribs, a pit rality of rings surrounding said ribs andcentered thereby but separate therefrom and "forming an annular wall,straining openings being provided in such wall, and an end piecedetachably secured to such base and holding said in place. said base,end piece, and ririgs inclosing a hollow space to which a flowconnection is provided in the structure.

2. A. strainer such as described comprising a base provided withintegral projecting ribs. a plurality of rings surrounding said ribs andcentered thereby but separate therefrom and forming an annular wall,straining openingsbeing provided in such wall, and an end piece screwconnected to "said ribs and holding said rings in place,

said base, end piece and rings inclosing a hollow space to which a flowconnection is provided in the structure.

3. A strainer such as described comprising a base provided 'withintegral projecting ribs and with a ring connecting said ribs near theends thereof, a. plurality of rings surrounding said ribs and forming anannular wall, straining openings being provided in such wall, andan endpiece screw connected to the ring connecting said ribs and holding saidwall-rings in place, said base, end piece and wall rings inclosing ahollow'space to which a flow connection is provided in the structure.

i. A strainer such as described comprising a base provided with integralproject ing ribs, av plurality of rings surrounding said ribs andcentered thereby but separate therefrom and forming an annular wall andspaced apart one from the other, whereby straining openings are providedin such walls, and an end piece detachably secured to such base andholding said rings in place,

said base, end piece and rings inclosing a hollow space to which a. flowconnection is provided in the structure.

A strainer such as described comprising a base provided with integralprojecting ribs, a plurality of rings surrounding said ribs and formingan annular wall and provided with bosses spacing said rings apart onefrom the other, whereby straining openings are provided in such wall,and an end piece detachably secured to such base and holding said ringsin place, said base,

end piece and rings inclosing a. hollow space to which a flow connectionis provided in the structure.

6. A strainer such as described co1npris ing a base, a plurality ofrings mounted thereon one above another and forming an annular wall andspaced apart one from another, whereby straining openings are providedin such wall, such rings being structurally separate from the base, saidbase provided with integral ribs for centering said rings, and an endpiece secured to such ribs and holding said rings in place, said base,end piece and rings inclosing a hollow space to which a flow connectionis provided in the structure.

in testimony whereof I have signed this specification in the presence oftwo subscribing witnesses.

ARTHUR- E. KRAUSE.

in. i. Mancini, D. A. DAVIES.

